Automatic circuit-breaker



(No Model.)

W. H. POWELL. AUTOMATIC CIRCUIT BRBAKER.

Patented Nov. l0, 1896.

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VILLIAM H. POVELL, OF HARTFORD, CONNECTICUT.

AUTOMATIC CIRCUIT-BREAKER.

SPECIFICATION forming part of Letters Patent No. 571,097, dated November 10, 1896.

Application filed June l5, 1896. Serial No. 595,546. (No model.)

T0 LZ whom, it may concer/2,:

Be it known that I, WILLIAM ll. POWELL, a citizen of the United States, residing atllartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Automatic Circuit- Breakers, of which the following is a specilication.

' The invention relates to the class ot electro mechanical devices which are constructed and arranged to automatically cut out circuits when the quantity of electricity in the mains which supply the circuits becomes abnorm ally large or above the desired maximum.

The object of the invention is to produce a simple, small, and cheap device of this class which can be conveniently connected with any light, power, heat, or similar circuit and readily adjusted to the desired capacity, so as to surely operate and cut out the circuit in which it is connected the instant the current supplied for any reason becomes greater than the limit of safety for the apparatus connected in the circuit.

To this end the device consists in a rotary cnt-out having conducting parts adapted to connect and disconnect stationary contacts or brushes with a spring that normally holds the conducting parts disconnected from the contacts, and a handle for turning the conducting parts into connection with the con tacts and making tense the spring, and an eleetromagnet withitscoilsconnectedinseries with the mains that pass to and are connected with the contacts of the cut-out, a weighted armature arranged to stand normally away from the magnet and be drawn to it when the current is greater than the predetermined maximum, at which time the current will be suitiiciently strong to cause the magnet to draw the armature against its counter attraetion, and a lever or latch connected to and movable with the armature and adapted to engage and retain the rotary parts of the cutout when they are so turned that the spring is made tense and the conducting parts join the contacts, as more particularly hereinafter described, and pointed out in the claims.

Referring to the accompanying drawings, Figure l is a side view of the device with the cut-out engaged by the latch, the spring tense, and the conducting parts connecting the contacts and completing the circuit through the cut-out, the case in which the device is usually inclosed being removed. Fig. is a view of the same, showing the magnet cut in central section, the armature drawn to the magnet, and the rotary parts of the cut-out in the position occupied after being released from the latch and thrown by the springthat is, with the conducting parts disconnecting the contacts that are connected with the circuitmains. Fig. 3 is a central section of the cutout on plane denoted by the broken line of Fig. l..

The device may be inclosed in a wooden or metal box or case or simply attached to a back board,as desired,which,however, is not shown in the views, as it can be of any shape and construction.

The base l of the cut-out can be made circular, of wood, porcelain, or any other suitable insulating material, and attached to the back of the case or board in any convenient manner. On the face of the base are secured the contacts, to which the circuit-wires are connected. The contacts 2 are preferably formed as 'Iiat plates, while the contacts 3 are Yformed as brushes that project with a little spring above the plates.

The base at the center supports a post l. This post is iirmly secured in position against rotation, and it loosely supports a block 5. The post bears a spiral spring 6, one end of which is connected with the post and the other is connected with the block or an arm that projects from the block. The block is free to rotate upon the post, except as controlled by this spring. The spring is made ot' considerable length, so that it will have the ncc essary power when made tense to throw the block quickly to obviate arcing, and yet will remain under tension for some time without being so strained as to lose its elasticity.

Connected with the block 5 is a disk 7, oit insulating material, which bears the conducting parts S, that when the d isl is in one position connect the contacts and brushes on the base and when the disk is in another position disconnect the contacts and brushes. The disk is so connected with the block that the conducting parts it bears connect the contacts and brushes when the spring is under tension. A handle 9 is attached to the block IOO or to a part projecting therelrom, and by means ol' this handle the block with the connected disk and conducting parts which the disk bears may be rotated. Secured to the base below the block is a disk 20, having lugs 21 arranged to engage the end oi the block and limit the distance oi' its rotary movement.

rThe magnet is secured to the back of the case by any suitable means. ln the term shown one of the circuit-wires that is connected with one of the contacts of the cut-out is coiled on a bobbin 11 into a solenoid and the whole encased in a cylinder 12, se as to form an iron-clad magnet. The armature is preferably formed with a core 13 and a `flanged head 1l, and the core is preferably bored out or made with a chamber 15, into which pieces of lead orsimilar non-magnetic metal can be pla-ced to adjust the weight of the armature. An opening can be made through the top et the magnet, through which the pieces ot nonmagnetic metal can be dropped into the chamber in the core.

Connected with the armature is a screw or stud 1li. The shank of this screw extends loosely through a perforation in the latchlever 17, and its head is arranged so that the armature mayhave a limited movement without moving the latch; but the armature cannot move its full distance without causing the head o'l the screw to engage the latch and move it. The latch 17 is preferably pivoted to the back of the ease, or a post extending therefrom, between the cut-out and the magnet, and theend opposite to that which is engaged bythe screw projecting from the armature is recessed or provided with a hook 1S, that may be made to engage and hold a part ot' the block that is mounted on the post of the cut-out. A pin, stud, or post 19 may be connected with the case to limit the movement of the latch in one direction.

\Vhen there is only the normal amount of current and of course when there is no current, passing through the circuit-wires, the armature is not attracted by the magnet, and by gravity it drops away from the pole of the magnet. Then the armature is away from the magnet, it engages the end of the lever and causes that end to be depressed, which of course raises the opposite end or the latch end oi' the lever. lith the latch in this position when the block mounted on the base or" the cutout is rotated by means of the handle the hooked end will engage the portion et the block when the spring is made tense and reta-in the block in this position with the spring in that eondition,as shown in Fig. 1. As above stated, when the block is in this position and the spring is tense the conducting parts connect the brushes and contacts on the base and com* plete the circuit through the cut-out. rihe parts are adjusted to remain this way as long as a normal current is passing through the mains, but when the current becomes abnor` mal or above the safety limit in quantity the magnet becomes of sufficient strength to draw the armature against the counter l'orce, which in the .form shown. is gravity, and this ot' course moves the end el the lever in such manner as to cause the latch end to disenga-ge from the block, which is then quickly thrown by the spring. 3y this action the conducting parts connected with the block are caused to suddenly disconnect the contacts and brushes and open the circuit. The parts remain in this position with the circuit open until the handle is again turned so the spring is made tense and the block engaged by the latch.

The armature, being loosely connected with the end of the latch-lever, is tree to move without the load of the lever for a portion olf its travel, that is, until it nearly reaches the pole of the magnet, where the strength ofthe pull is greatlyinereased, so that a stron g pull may be exerted upon the end of the lever for causing it to unlatch from the block ot the cut-out. This construction allows the armature to move Vfreely until it has developed considerable speed and the power of the magnetic pull has increased so that the armature will have considerable momentum and will give the end et' the lever such a blow as will cause it to surely move and free itsell' from the block. rllhe weight ot the armature can be adjusted and its distance from the pole of the magnet regulated so that it will remain down until just the amount of current required to litt it is passing through the coils of the magnet. rlhe 'further the armature is from the pole of the magnet the more delicately can it be regulated, so that just the amount of pull to start it toward the magnet can be nicely determined. The armature may be allowed to drop to such a distance from the pole of the magnet that the pull when the armature is first drawn is comparatively weak,but when the latch-leveris engaged and moved the armature is so near thepole ol the magnet that the pull is quite stron The drawings show a double-pole cut-out; but the device can be arranged in the same manner with a single-pele cut-out.

The device is simple, cheap, and easily connected with any kind el a circuit, whether it be a lighting-circuit, heating-circuit, or a power-circuit. rlhe cut-out operates with a very quick movement and will open the circuit without arcing. The magnet is sure in action, and the armature can be readily regulated and adjusted so that it will operate with the exact predetermined amount ot' current. The cut-out is easily set and will always pcrmit the passage o.l` a normal amount of current, but will surely break the circuit when released from the hold ol? the armature-cm` trolled latch-lever.

The magnet shown in the drawings is wound by coils of the main circuit-wires; but et course the magnet may be wound by coils sh unted from the main circuit-wire.

l claim as my inventionm 1. in a circuitdncaker, in combination, a cut-out having stationary contacts adapted to IOO IIO

IZO

be connected with circuit-wires, a rotary spin-v dle,rotary connecting and disconnectin g parts supported by the spindle, a spring f or rotatin g the spindle in one direction and a handle for rotating the spindle in the opposite direction, a latch adapted to engage the spindle for holdin g the spindle with the spring under tension, an electromagnet with its coils adapted to be connected in series with the circuit-wires, and an armature loosely connected by an adjustable connection with the latch in such manner that the connection can be regulated so the armature will move independently of the latch for a predetermined portion oi' its travel and for the predetermined remainder of its travel engage with and pull the free end of the latchlever toward the magnet, said armature being normally held down by gravity and adapted to be drawn upward by the pull of the inagnet, substantially as specified.

2. In a circuit-breaker, in combination, a cut-ont having stationary contacts adapted to be connected with circuit-wires, rotary connecting and disconnecting parts, a spring for rotating the connecting and disconnectingI parts in one direction and aliandle for rotating them in the opposite direction7 a gravitylatch for holding the connecting and disconnecting parts with the spring nnder tension, and an armature with a recess for receiving non-magnetic metal, said armature being loosely connected with the gravity-latch by an adj nstable connection, and an electromagnet with its coils adapted to be connected in series with the circuit-wires7 snbstantiallyas specified.

In. a circuit-breaker7 in combination, a rotary cnt-ont having stationary contacts adapted to be connected with circuit-wires, a station ary post supporting a rotary block with a disk of insulating material bearing connecting and disconnecting parts, a spring connected with the post and with the rotary block, a handle connected with the block, a latch arranged to engage and hold the block with the spring under tension, a hollow armature with a screw loosely connecting the armature and the latch-lever, and a solenoid with its coils adapted to be connected in series with the eircnit-wires, substantially as speciiied.

VILLIAM H. POXVELL. lilitnesses:

Il. R. WILLL-ins, E. I. HYDE. 

